The central aims of this application are to clarify the subjective responses to informed consent in clinical research involving individuals with five serious psychiatric and medical illnesses and to determine whether educational interventions based on such data can enhance investigators' knowledge and skills related to research conducted with vulnerable study participants. The application includes consideration of cognitive, informational, and subjective factors which may influence informed consent and participation in research projects. This project includes two studies. Study 1 utilizes two structured interviews with research participants diagnosed with schizophrenia, major depression, post traumatic stress disorder, lung cancer, or advanced HIV/AIDS and healthy comparison subjects. Based on the data generated from Study 1, Study 2 will use these data to design an educational intervention for clinical investigators. The educational workshops for the investigators will focus on guidelines related to research ethics and informed consent as well as to review the diagnosis-specific subjective responses of the vulnerable research participants and analogous data of investigative perceptions from Study 1. The control workshop will provide only diagnosis-specific demographic information. Study 2 is to determine whether or not information given to investigators regarding attitudes, motivations, expectations, and perceptions of suffering and values of patients will increase their awareness, understanding, problem identification skills and behavior intentions regarding informed consent and ethical approach to aspects of research.